1988 Convertible for sunny day drives
- Thread starter Tourmax
- Start date
- Thread starter
- #102
My steering wheel was showing it's age. Only 120,000 kms on the car, but it seems the steering wheel was held mainly buy the upper portion.
The leather was still intact,but it looked like, well...... chit.
Faded, dirty and the leather was beginning to show the early signs of one day doing the full on split, tear and sloughing off the wheel completely.
Here's a pic where you can see it's more of a dull gray color than black:
What you can't see is how the leather is worn and starting to show signs of cracking from decades of grubby little hands holding it and the sun drying/baking/beating the crap out of it. Just a mess overall.
I had considered stripping it and putting a new leather cover on it, but I figured I'd give it a go to try and make it look half decent and save myself the aggravation of trying to recover the wheel, at least for a few more years.
With nothing to loose, I thought I'd give a trick I'd learned many moons ago a try.
First, I took rubbing alcohol and gave the wheel a good cleaning to get decades of skin oil, dead skin build up, dirt - and gawd knows what else - off the wheel. The alcohol cleans the grubbiness off, pulls the skin oils up to the surface and helps open the pores of the leather for the next step.
Then you take a little lacquer thinner and wet down a white, lint free rag. You want white so it doesn't transfer any color to the leather wheel other than the color you want. The "lint free" part is self explanatory.
Then you take your spray leather dye and spray the rag over the lacquer thinner until its good and saturated. What you've just created is a nice, thinned down leather dye that will penetrate the leather, flow evenly and swell the leather back up to like it was prior to the sun (and oily hands) drying it out. You want your leather dye/paint thinned down so that when you put it on the wheel it penetrates the leather instead of sitting on the surface, where it can eventually wear, peel and flake off.
I then took my rag/solution and rubbed the wheel down. First application looked a little better. I let it dry and applied the solution several more times. After about 5 or so treatments, the wheel looks like this:
Not too bad! It's not perfect, but it almost looks like a new wheel. A few more applications and it should look jammy! It was hard to get a picture of it that does it justice (because of the light shining into the garage through the door windows), so you'll have to take my word that it looks 10x better than it did.
The shine is all "natural". There's no product on the wheel except for my leather dye concoction. It needs a few more coats to get it good and smooth and an even coloring across the wheel. The top is still a little dull looking but you can tell it's going to come around witha few more applications. The leather just keeps soaking in that dye!
But, for an modest investment of time and effort, it should come around good enough to use for another 5-10 years.
The leather was still intact,but it looked like, well...... chit.
Faded, dirty and the leather was beginning to show the early signs of one day doing the full on split, tear and sloughing off the wheel completely.
Here's a pic where you can see it's more of a dull gray color than black:
What you can't see is how the leather is worn and starting to show signs of cracking from decades of grubby little hands holding it and the sun drying/baking/beating the crap out of it. Just a mess overall.
I had considered stripping it and putting a new leather cover on it, but I figured I'd give it a go to try and make it look half decent and save myself the aggravation of trying to recover the wheel, at least for a few more years.
With nothing to loose, I thought I'd give a trick I'd learned many moons ago a try.
First, I took rubbing alcohol and gave the wheel a good cleaning to get decades of skin oil, dead skin build up, dirt - and gawd knows what else - off the wheel. The alcohol cleans the grubbiness off, pulls the skin oils up to the surface and helps open the pores of the leather for the next step.
Then you take a little lacquer thinner and wet down a white, lint free rag. You want white so it doesn't transfer any color to the leather wheel other than the color you want. The "lint free" part is self explanatory.
Then you take your spray leather dye and spray the rag over the lacquer thinner until its good and saturated. What you've just created is a nice, thinned down leather dye that will penetrate the leather, flow evenly and swell the leather back up to like it was prior to the sun (and oily hands) drying it out. You want your leather dye/paint thinned down so that when you put it on the wheel it penetrates the leather instead of sitting on the surface, where it can eventually wear, peel and flake off.
I then took my rag/solution and rubbed the wheel down. First application looked a little better. I let it dry and applied the solution several more times. After about 5 or so treatments, the wheel looks like this:
Not too bad! It's not perfect, but it almost looks like a new wheel. A few more applications and it should look jammy! It was hard to get a picture of it that does it justice (because of the light shining into the garage through the door windows), so you'll have to take my word that it looks 10x better than it did.
The shine is all "natural". There's no product on the wheel except for my leather dye concoction. It needs a few more coats to get it good and smooth and an even coloring across the wheel. The top is still a little dull looking but you can tell it's going to come around witha few more applications. The leather just keeps soaking in that dye!
But, for an modest investment of time and effort, it should come around good enough to use for another 5-10 years.
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- Thread starter
- #103
Does it look new? Well, no. It does not::
But it looks a damned sight better than it did!
It took another 3 applications of the dye to get it all a uniform black, but patience and determination always wins out! If you zoom in on the pic, you can see some of the lines in the leather. But unless you are right up on it and looking for them, you don’t really notice them.
That will do me for a while I think! Looks good!
Only problem is now the shifter knob and boot look a little “shabby”. Guess I’ll have to make up some more laquer thinner and dye solution and go at them too!
But it looks a damned sight better than it did!
It took another 3 applications of the dye to get it all a uniform black, but patience and determination always wins out! If you zoom in on the pic, you can see some of the lines in the leather. But unless you are right up on it and looking for them, you don’t really notice them.
That will do me for a while I think! Looks good!
Only problem is now the shifter knob and boot look a little “shabby”. Guess I’ll have to make up some more laquer thinner and dye solution and go at them too!
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Good thing you can do all the work yourself. I'd not it would if cost you a fortune to get all the work done. 
- Thread starter
- #105
Oh, I’ve always been a DIY guy. With everything from cars and trucks to building houses and landscaping.Good thing you can do all the work yourself. I'd not it would if cost you a fortune to get all the work done.
For example, here’s the latest landscaping project at the front of the house (house is about 1.5 years old now):
Designed it, picked out all the plantings and fixtures and then built it all by myself. Wife has no head or eye for landscaping and she’s a skinny little 120 lb blonde girl, so it was all on me or nothing.
And, because I’m so busted up after 29 years of flying SAR, there was no way I was going to be able to do it by hand power and wheelbarrow. Once upon a time, I would have been able to “grunt work” it all out with just a shovel and wheelbarrow, but not anymore. Too old, too broken. So I built this:
Out of this:
Picked the tractor up for a hundred bucks. It didn’t run and needed lots of work, but it was a garden tractor as opposed to a ride on lawn mower, so I had some decent base material to build on (bigger tires and rims, thicker frame, ground engaging transmission, B&S 20 hp opposed twin, etc). I dropped a couple hundred on some used bits (like an atv plow blade), some new steel stock, sprinkled well with a mig welder “pixie dust”, some electrical work and a splash of paint and I had a small tractor that could landscape, dig and move rock/dirt/things around that I couldn’t bulge by hand. All in; I’ve got somewhere around 600-700 bucks invested in it. Waaaay less than it would have cost for a SCUT with a front loader (at least 30-40 grand). I did the entire lot, front and back with it. Its a wonderful thing when you can build things yourself.
Or, maybe I’m just too cheap to pay someone else to do something I could do myself!
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You know the old saying about teaching a man to fish? That seems to be you. With all the yahoos on YouTube, you could probably start up your own channel for the @Home DIY'ers with the various projects you undertake and make some money in the process. Show them a thing or two.
Not sure why, but this is one thread I look forward to reading to see what you're going to handle next on the C4 and miss it when there isn't any new posts. And now that you've introduced us to other projects, I look forward to reading it even more. LOL. Keep up the good work.
Not sure why, but this is one thread I look forward to reading to see what you're going to handle next on the C4 and miss it when there isn't any new posts. And now that you've introduced us to other projects, I look forward to reading it even more. LOL. Keep up the good work.
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- Thread starter
- #107
Thanks, very kind of you.You know the old saying about teaching a man to fish? That seems to be you. With all the yahoos on YouTube, you could probably start up your own channel for the @Home DIY'ers with the various projects you undertake and make some money in the process. Show them a thing or two.
Not sure why, but this is one thread I look forward to reading to see what you're going to handle next on the C4 and miss it when there isn't any new posts. And now that you've introduced us to other projects, I look forward to reading it even more. LOL. Keep up the good work.
Here’s a “build thread” on the tractor if you are interested in knowing more a out it.
The yard is...well, just a yard. Moving rocks and dirt and plants to where you want them.
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- Thread starter
- #108
continued from: About 4 weeks in, having some serious thoughts about modifications......
So i'm looking at options to modify the L98. I don't particularly want to take too much away from it on the bottom end to reach an ultimate HP number, so there's going to be compromises somewhere.
I'm shooting for around 300-350 at the crank, so my goals are fairly modest. somewhere around stock LT1 numbers. But this is a street car and I want it to stay that way so a high reving screamer is out of the question. No sense making 400 HP if you have to spin it to 6G to get it. that's not where this car will live.
Aftermarket stuff like a FAST TPI setup would be great, but I don't really have that kind of money to drop all at once. The FAST system is going to tickle 2G CAD by the time I get it at my door and I'm (IE: bank account) not up for that.
I've got a complete LT1 intake:
I grabbed it used for 75 bucks. Intake, rails, injectors, etc. Couldn't pass it up at that price. I am considering altering as required (distributor hole, water ports, bolt holes, etc) and using it, but with 3.5" long runners, I'm worried it will adversely effect low end torque production, where the car spends most of it's time. I'm also not thrilled with the thought of using a remote thermostat housing and I don't particularly like the fact that you have to take the water from the heads from either the front of the rear of the heads when the L98 has coolant crossovers in front and back of the L98 TPI lower. Using the HEi distributor also means loosing all the EGR stuff (no room), which doesn't give me that good "no smog" feeling.I live in atlantic Canada and have experienced being the USA's "tailpipe"more than once in the summers and don't wish that crap on anyone. The good news is even if I loose the EGR stuff, I can get it back by using a cam that allows enough overlap to perform the same function as the egr valve (IE: LT4 has no egr valve, all done in cam design).
I'm also now considering altering the LT1 rather radically". I'm thinking to chop the front and back off the LT1 intake, take one of the spare TPI lower manifolds I have lying around and chopping the front and back off that. Then, once bolted firmly in a jig, wled the L98 pieces to the LT1 piece. That will give me an LT1 style runner/plenum piece, yet retain the water passage crossovers, the front mounted thermostat hosing and the rear distributor hole. I'd still loose the EGR bits, but again, I can handle that with cam timing.
the next option is to "customize" the OEM L98 TPI stuff. I'd take another spare TPI lower I have and port it out as much as possible. Then, after a tedoulsy long set of calculations, decide on a runner length and diameter that will put the power curves where I want them. The OEM runners are about 21" in length (to the intake valve), which is tuned the way GM engineers wanted it. I've also done some quick calcs and the OEM TPI is indeed sized for a 305, so it's leaving something on the table on a 350. Calcs seem to indicate I need a 1.7" runner instead of a 1.5" runner to feed a 350 rather than a 305. Calculating out the runner length will put the torque and HP at the rpm ranges where I decide I want it. Shortening the tube runners isn't a big issue. I'll just machine off the oem tubes, open up the flanges and weld in new mandrel bends. To deal with shorter runners, I'll just cut the sides off the OEM plenum and add "filler material" to bring the sides of the plenum down to meet where the runners end. Effectively, I'll be adding to the plenum volume while simultaneously shortening the runners. I'm hoping to end up with runners somewhere around LSx territory (around 12"), but I'll have to see what the formulas spit out. On the plus side, it will look nearly stock and mostly retain the TPI look (which I like, it's period correct).
The Last option is to just port out the OEM TPI and try and see if I can source some larger runners. I could make them, but if they are going to be stock lengths, I'd just a soon buy a pair, port match them to the upper/lower and bolt it togther.
An aftermarket lower would be nice, but they're no longer made and anything used seems to be asking OH MY GOD! prices.
So i'm looking at options to modify the L98. I don't particularly want to take too much away from it on the bottom end to reach an ultimate HP number, so there's going to be compromises somewhere.
I'm shooting for around 300-350 at the crank, so my goals are fairly modest. somewhere around stock LT1 numbers. But this is a street car and I want it to stay that way so a high reving screamer is out of the question. No sense making 400 HP if you have to spin it to 6G to get it. that's not where this car will live.
Aftermarket stuff like a FAST TPI setup would be great, but I don't really have that kind of money to drop all at once. The FAST system is going to tickle 2G CAD by the time I get it at my door and I'm (IE: bank account) not up for that.
I've got a complete LT1 intake:
I grabbed it used for 75 bucks. Intake, rails, injectors, etc. Couldn't pass it up at that price. I am considering altering as required (distributor hole, water ports, bolt holes, etc) and using it, but with 3.5" long runners, I'm worried it will adversely effect low end torque production, where the car spends most of it's time. I'm also not thrilled with the thought of using a remote thermostat housing and I don't particularly like the fact that you have to take the water from the heads from either the front of the rear of the heads when the L98 has coolant crossovers in front and back of the L98 TPI lower. Using the HEi distributor also means loosing all the EGR stuff (no room), which doesn't give me that good "no smog" feeling.I live in atlantic Canada and have experienced being the USA's "tailpipe"more than once in the summers and don't wish that crap on anyone. The good news is even if I loose the EGR stuff, I can get it back by using a cam that allows enough overlap to perform the same function as the egr valve (IE: LT4 has no egr valve, all done in cam design).
I'm also now considering altering the LT1 rather radically". I'm thinking to chop the front and back off the LT1 intake, take one of the spare TPI lower manifolds I have lying around and chopping the front and back off that. Then, once bolted firmly in a jig, wled the L98 pieces to the LT1 piece. That will give me an LT1 style runner/plenum piece, yet retain the water passage crossovers, the front mounted thermostat hosing and the rear distributor hole. I'd still loose the EGR bits, but again, I can handle that with cam timing.
the next option is to "customize" the OEM L98 TPI stuff. I'd take another spare TPI lower I have and port it out as much as possible. Then, after a tedoulsy long set of calculations, decide on a runner length and diameter that will put the power curves where I want them. The OEM runners are about 21" in length (to the intake valve), which is tuned the way GM engineers wanted it. I've also done some quick calcs and the OEM TPI is indeed sized for a 305, so it's leaving something on the table on a 350. Calcs seem to indicate I need a 1.7" runner instead of a 1.5" runner to feed a 350 rather than a 305. Calculating out the runner length will put the torque and HP at the rpm ranges where I decide I want it. Shortening the tube runners isn't a big issue. I'll just machine off the oem tubes, open up the flanges and weld in new mandrel bends. To deal with shorter runners, I'll just cut the sides off the OEM plenum and add "filler material" to bring the sides of the plenum down to meet where the runners end. Effectively, I'll be adding to the plenum volume while simultaneously shortening the runners. I'm hoping to end up with runners somewhere around LSx territory (around 12"), but I'll have to see what the formulas spit out. On the plus side, it will look nearly stock and mostly retain the TPI look (which I like, it's period correct).
The Last option is to just port out the OEM TPI and try and see if I can source some larger runners. I could make them, but if they are going to be stock lengths, I'd just a soon buy a pair, port match them to the upper/lower and bolt it togther.
An aftermarket lower would be nice, but they're no longer made and anything used seems to be asking OH MY GOD! prices.
12cents
Power User
I don't remember who made them but at one time you could get a TPI intake with Siamese runners that would look almost stock to the casual person. I am not sure if that would be a solution to your dilemma or even if it is possible to make something up in a similar vein. I have seen TPI intakes with larger runners than stock and I had to look twice to be sure of what I was looking at. You have some wicked skills so I am sure something will be made to fulfill what you want. Looking forward to your solution.
- Thread starter
- #110
If I go custom TPI, will probably look like what this gent did:
Those are 2" runners IIRC and the plenum modified to reach down to meet them. He chopped about an inch off the runners and the plenum was altered to reach down to meet them. He shortened the runners and increased plenum volume at the same time. The base was a ported accel unit, opened up to 1.875". I don't think I can open up an OEM lower that much, or I'll probably need to add some weld if I do. I won't be going mono-blade TB. I've got an ASM 52MM TB to bolt on to it and that's a twin blade TB.
He pulled 421 Hp with a prototype for this design (with full length runners and stock plenum), although no numbers on the final intake design above. The engine wasn't exactly stock though, 369 cid, AFR heads, etc.
I'm planning to do the intake, a cam and exhaust work. Hopefully, 300-350 crank is "doable" on my relatively mild setup. I'm also pro "stock look" for the TPI setup. I'd like someone to do a "second look" to actually figure out what they just saw.....
- Thread starter
- #111
Getting all the donor parts together:
Good start there. Lota of raw material to make both the LT1 conversion and the “mega tpi” manifolds.
I know I’ve got more tpi stuff lying around, but I just don’t feel like digging through my shelves anymore right now.
Now, to start looking for a local source for mandrel bent AL tubing....that’s going to be a fairly tall order around here.
That's a 7427 PCM sitting in the pic. It's an OBD PCM capable of controlling both PFI and electronic transmissions............
Good start there. Lota of raw material to make both the LT1 conversion and the “mega tpi” manifolds.
I know I’ve got more tpi stuff lying around, but I just don’t feel like digging through my shelves anymore right now.
Now, to start looking for a local source for mandrel bent AL tubing....that’s going to be a fairly tall order around here.
That's a 7427 PCM sitting in the pic. It's an OBD PCM capable of controlling both PFI and electronic transmissions............
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- Thread starter
- #112
Alrighty. since the LT1 intake is mainly just cutting and welding, I'm going to start on that first. A couple side by side pics:
So, things that need to be done:
1. Modify the rear of the LT1 for ;
a. Distributor hole
b. Shave off/alter the EGR bosses for space to fit the HEI distributor
2. Coolant crossover and thermostat housing needed
3. bolt holes to be moved/altered
4. TB mounting to be altered
5. Throttle and TV cables to be sorted and mounted
6. Fuel lines
7. Adjustable Fuel pressure regulator.
8. LT1 TB linkage to be sorted/altered
9. TPS to be sorted (LT1 is different than the L98)
First of all, let me say I'm not reinventing the wheel here. LT1 swaps on to an L98 has been done for more than a decade now and been accomplished many different ways. Essentially, you're making your own mini-ram" manifold. The TPiS mini-ram is rumored to have been made as a copy of the LT1 intake and released a few months before the LT1 came out.
1. a. Distributor hole:
Couple options here. You can cut the distributor hole and install an angled spacer with hold down bolt, or you can cut the whole back of the manifold off and weld on the L98 rear, or you can cut out just the dist hole from an old TPI manifold and weld that in:
I'm leaning towards doing either the whole rear of the manifold or cutting out the dist hole and welding it into the LT1 intake. Using the whole back of hte TPI manifold keeps the Distributor in the correct location, it moves the proper holes for mounting to the LT1 intake and ensures enough "meat" to cover over the 113 head cooling passage. Whichever way I go, the manifold will have to be bolted into a steel jig to keep the warping to a minimum. Aluminum will move like crazy when you weld it if not bolted firmly into a jig. Even then, I'll probably still have to have the sealing surfaces trued up after welding. Still thinking about if I want to do that myself or send it out.
1b. Shave EGR.
Well, no emissions testing here so I can "file 13" the EGR if I want. But, I'd like to keep it. The Maritimes experiences "smog" from the US (we're been called the US east cost's tialpipe) and I'd like to emit as few NOx particles as I can. EGR also helps with preventing knock and improving MPG. It's off at idle and WOT, so it has no effect ofn HP, like a lot of people thinks. The problem is the large cap HEI distributor won't clear the LT1 EGR bosses. Typically, most just shave the EGR right off:
That leaves plenty of room for the large cap HEI:
Unfortunately, EGR is essentially deleted. You can get away with teh smaller GM cap distributor and the remote col, but you still can't use the EGR valve due to clearance issues.
But, once upon a time, GM actually made a few design prototypes that used the LT1 intake on distributor engines:
Now, these are ultra rare and finding one is......well, impossible. I'm betting it was for the marine division to use the LT1 in a boat application, but the LSx (marine) probably put a stop to that design line. But the design is what interests me. The egr Bosses are well out of the way of a distributor and it's nearly the same EG "in" port as the L98 with 113 heads. When I chop off the bosses, I'm going to look at welding the manifold back up with the EGR bosses like the GM prototype and try to retain EGR. If I can't, I'll go to a cam like the LT4 specs, where EGR is a function of the cam's overlap and reversion of EG into the combustion chamber. The LT4 has no EGR valve because it manages it through the cam design.
2. Coolant passage crossover/Thermostat housing.
the LT1 intake is "dry". Meaning, no coolant passages and therefor, not thermostat housing. The LT1 has the housing built into the water pump. The usual fix for this is swap in a couple fittings in the head passages (front or rear), a couple hoses and a remote thermostat housing:
It may work, but man that just looks sooooo janky! I don't like stuff that looks tacked on or rigged up and that just won't work for me. It may be functional, but it would drive me crazy knowing that was under the hood like that. High probability of it coing loose and contacting the serptine belt system as well. So I'm going to look at chopping up the front of the LT1 intake and adding the coolant passages with the thermostat housing. Here's an image where someone took one of those prototype LT1 intakes and added a passage and thermostat housing:
As you can tell, it's been pretty extensively reworked but it looks a lot better than that remote housing "zap strapped" to the engine.
3. Intake bolt holes.
The LT1 has the "new" bolt hole angles. Meaning, they enter the head at a 72 degree angle as opposed to the SBC/113 heads which enter the heads at a 90 degree angle to the gasket surface. In welding on the front and rear of the TPI lower manifold, that means those 8 holes will already be changed to the proper 113 intake bolt angles. The center 4 bolts (two per side) are easily re-drilled. The center holes are also in the wrong place for the SBC/113 heads. That's an easy fix; weld 'em up and re-drill them in the correct spot.
4. TB relocation.
As you can see in the comparison pics at the top, the LT1 TB flange is more forward and lower than the L98 TPI plenum mount. That's a problem for adding the thermostat housing, it moves the throttle body into conflict with some of the accessory bracket and being too low causes another problem:
'
You can see the Vette MAF ducting has to be pretty "cranked" to mate the stock LT1 TB location to the MAF ducting. And, while the slightly forward location of the LT1 TB compared to the TPI might not seem like an issue (because the ribbed duct can be compressed slightly), it also means the throttle cable is too short. but more importantly, the 700r4 V cable is no longer going to fit properly. So the TB has to move up and back on the LT1 intake.
Luckily, the guy with the prototype LT1 intake has also shown that it can be moved:
Cut, reposition and weld. Easy peasy. You loose a little plenum volume, but it still dwarf's the L98 plenum volume. I've got a possible plan in mind to add plenum volume as well, so it should come out bigger (or about even) than the stock LT1.
5. Throttle and TV cables to be sorted and mounted
Most of that will be fixed with moving the TB mount on the plenum, but I will still have to measure and mount the TPI cable bracket to maintain the proper alignment. Critically important for the TV valve to not burn up the 700r4. The LT1 throttle body also has the wrong bracket on it to take the L98 cables. That will be a simple swap from an old TPI TB to the LT1 TB from AS&M.
6. Fuel lines
Obviously, the LT1 lines are not compatible with the L98 lines. The LT1 is on the drivers side rear and the L98 is the passenger side front. You can buy kits that fix this, but I may just build my own and change it to a parallel fuel rail at the same time.
7. Adjustable Fuel pressure regulator.
Yep, need one. If I plumb my own lines, adding one is easy and I can mount it wherever I want.
8. LT1 TB linkage to be sorted/altered
Talked about it in #7. Bascially, swap the brackets from the L98 TB to the LT1 TB.
9. TPS to be sorted (LT1 is different than the L98)
So, the LT1 TPS is different thant the TPI. Different mounting on the TB, different electrical connector. Luckily, the LT1 TPS puts out the same signal as the TPI TPS, so it's just a matter of swapping out the TPI connector for the LT1 connector.
There's a bunch oif little things to be addressed like vaccum ports, PCV setups and that sort of stuff, but it's small little bits that is usually easily handled by welding up some ohomes and drilling/tapping new ones.
Well, that's enough talking about it. Time to start cutting stuff up!
So, things that need to be done:
1. Modify the rear of the LT1 for ;
a. Distributor hole
b. Shave off/alter the EGR bosses for space to fit the HEI distributor
2. Coolant crossover and thermostat housing needed
3. bolt holes to be moved/altered
4. TB mounting to be altered
5. Throttle and TV cables to be sorted and mounted
6. Fuel lines
7. Adjustable Fuel pressure regulator.
8. LT1 TB linkage to be sorted/altered
9. TPS to be sorted (LT1 is different than the L98)
First of all, let me say I'm not reinventing the wheel here. LT1 swaps on to an L98 has been done for more than a decade now and been accomplished many different ways. Essentially, you're making your own mini-ram" manifold. The TPiS mini-ram is rumored to have been made as a copy of the LT1 intake and released a few months before the LT1 came out.
1. a. Distributor hole:
Couple options here. You can cut the distributor hole and install an angled spacer with hold down bolt, or you can cut the whole back of the manifold off and weld on the L98 rear, or you can cut out just the dist hole from an old TPI manifold and weld that in:
I'm leaning towards doing either the whole rear of the manifold or cutting out the dist hole and welding it into the LT1 intake. Using the whole back of hte TPI manifold keeps the Distributor in the correct location, it moves the proper holes for mounting to the LT1 intake and ensures enough "meat" to cover over the 113 head cooling passage. Whichever way I go, the manifold will have to be bolted into a steel jig to keep the warping to a minimum. Aluminum will move like crazy when you weld it if not bolted firmly into a jig. Even then, I'll probably still have to have the sealing surfaces trued up after welding. Still thinking about if I want to do that myself or send it out.
1b. Shave EGR.
Well, no emissions testing here so I can "file 13" the EGR if I want. But, I'd like to keep it. The Maritimes experiences "smog" from the US (we're been called the US east cost's tialpipe) and I'd like to emit as few NOx particles as I can. EGR also helps with preventing knock and improving MPG. It's off at idle and WOT, so it has no effect ofn HP, like a lot of people thinks. The problem is the large cap HEI distributor won't clear the LT1 EGR bosses. Typically, most just shave the EGR right off:
That leaves plenty of room for the large cap HEI:
Unfortunately, EGR is essentially deleted. You can get away with teh smaller GM cap distributor and the remote col, but you still can't use the EGR valve due to clearance issues.
But, once upon a time, GM actually made a few design prototypes that used the LT1 intake on distributor engines:
Now, these are ultra rare and finding one is......well, impossible. I'm betting it was for the marine division to use the LT1 in a boat application, but the LSx (marine) probably put a stop to that design line. But the design is what interests me. The egr Bosses are well out of the way of a distributor and it's nearly the same EG "in" port as the L98 with 113 heads. When I chop off the bosses, I'm going to look at welding the manifold back up with the EGR bosses like the GM prototype and try to retain EGR. If I can't, I'll go to a cam like the LT4 specs, where EGR is a function of the cam's overlap and reversion of EG into the combustion chamber. The LT4 has no EGR valve because it manages it through the cam design.
2. Coolant passage crossover/Thermostat housing.
the LT1 intake is "dry". Meaning, no coolant passages and therefor, not thermostat housing. The LT1 has the housing built into the water pump. The usual fix for this is swap in a couple fittings in the head passages (front or rear), a couple hoses and a remote thermostat housing:
It may work, but man that just looks sooooo janky! I don't like stuff that looks tacked on or rigged up and that just won't work for me. It may be functional, but it would drive me crazy knowing that was under the hood like that. High probability of it coing loose and contacting the serptine belt system as well. So I'm going to look at chopping up the front of the LT1 intake and adding the coolant passages with the thermostat housing. Here's an image where someone took one of those prototype LT1 intakes and added a passage and thermostat housing:
As you can tell, it's been pretty extensively reworked but it looks a lot better than that remote housing "zap strapped" to the engine.
3. Intake bolt holes.
The LT1 has the "new" bolt hole angles. Meaning, they enter the head at a 72 degree angle as opposed to the SBC/113 heads which enter the heads at a 90 degree angle to the gasket surface. In welding on the front and rear of the TPI lower manifold, that means those 8 holes will already be changed to the proper 113 intake bolt angles. The center 4 bolts (two per side) are easily re-drilled. The center holes are also in the wrong place for the SBC/113 heads. That's an easy fix; weld 'em up and re-drill them in the correct spot.
4. TB relocation.
As you can see in the comparison pics at the top, the LT1 TB flange is more forward and lower than the L98 TPI plenum mount. That's a problem for adding the thermostat housing, it moves the throttle body into conflict with some of the accessory bracket and being too low causes another problem:
'
You can see the Vette MAF ducting has to be pretty "cranked" to mate the stock LT1 TB location to the MAF ducting. And, while the slightly forward location of the LT1 TB compared to the TPI might not seem like an issue (because the ribbed duct can be compressed slightly), it also means the throttle cable is too short. but more importantly, the 700r4 V cable is no longer going to fit properly. So the TB has to move up and back on the LT1 intake.
Luckily, the guy with the prototype LT1 intake has also shown that it can be moved:
Cut, reposition and weld. Easy peasy. You loose a little plenum volume, but it still dwarf's the L98 plenum volume. I've got a possible plan in mind to add plenum volume as well, so it should come out bigger (or about even) than the stock LT1.
5. Throttle and TV cables to be sorted and mounted
Most of that will be fixed with moving the TB mount on the plenum, but I will still have to measure and mount the TPI cable bracket to maintain the proper alignment. Critically important for the TV valve to not burn up the 700r4. The LT1 throttle body also has the wrong bracket on it to take the L98 cables. That will be a simple swap from an old TPI TB to the LT1 TB from AS&M.
6. Fuel lines
Obviously, the LT1 lines are not compatible with the L98 lines. The LT1 is on the drivers side rear and the L98 is the passenger side front. You can buy kits that fix this, but I may just build my own and change it to a parallel fuel rail at the same time.
7. Adjustable Fuel pressure regulator.
Yep, need one. If I plumb my own lines, adding one is easy and I can mount it wherever I want.
8. LT1 TB linkage to be sorted/altered
Talked about it in #7. Bascially, swap the brackets from the L98 TB to the LT1 TB.
9. TPS to be sorted (LT1 is different than the L98)
So, the LT1 TPS is different thant the TPI. Different mounting on the TB, different electrical connector. Luckily, the LT1 TPS puts out the same signal as the TPI TPS, so it's just a matter of swapping out the TPI connector for the LT1 connector.
There's a bunch oif little things to be addressed like vaccum ports, PCV setups and that sort of stuff, but it's small little bits that is usually easily handled by welding up some ohomes and drilling/tapping new ones.
Well, that's enough talking about it. Time to start cutting stuff up!
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- Thread starter
- #113
Task for today was to get the jig built for the lt1 intake modifications:
Done!
The side rails are drilled for the lt1 bolt pattern to hold it in place for cutting and welding, but it is also drilled for the L98 intake bolt pattern. That way, I can cut off the front and rear bits of the LT1 manifold and weld on the l98 bits. The bolt holes will accurateky locate the L98 front and rear bits for welding and the center holes will allow me to accurateky drill the L98 holes in the LT1 manifold.
Now back to cutting and chopping...to be followed bu some AL welding....
Done!
The side rails are drilled for the lt1 bolt pattern to hold it in place for cutting and welding, but it is also drilled for the L98 intake bolt pattern. That way, I can cut off the front and rear bits of the LT1 manifold and weld on the l98 bits. The bolt holes will accurateky locate the L98 front and rear bits for welding and the center holes will allow me to accurateky drill the L98 holes in the LT1 manifold.
Now back to cutting and chopping...to be followed bu some AL welding....
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- Thread starter
- #114
Bolted into the jig and shaping it:
Screwed up my cuts a little bit, but I can fix that in the welding process. I arranged the cuts so that the area that needs welding is not a sealing area that will see pressure. It just seals the lifter valley.
Still a long way to go, but that’s a good start for the first day.
Screwed up my cuts a little bit, but I can fix that in the welding process. I arranged the cuts so that the area that needs welding is not a sealing area that will see pressure. It just seals the lifter valley.
Still a long way to go, but that’s a good start for the first day.
You definitatly know your stuff. Your doing a great job fixing all these things.
- Thread starter
- #116
Well, thats just total shite:
Porosity and low penetration everywhere.
Tried sandblasting, flap wheels, cleaners, preheating and even several wipe downs with lacquer thinner and acetone. No dice. That cast just will not take a good weld. I can see where the contaminants are trying to “bubble up” through the weld puddle and just ruining everything. It’s so bad, I can’t even get a puddle to form properly to run a decent bead.
Only thing I can think of is to drop it in the oven at around 300-400F for a couple hours and try to boil the contaminants out of the porous aluminum casting so I will have at least a fighting chance of getting it to will weld properly.
Jeez, what a mess. At this rate, I might be chucking the whole LT1 intake in the trash (well, actually, I’ll prob end up just smelting it down to ingots).
I just might end up sticking with the oem TPI or maybe trying to find a used mini ram or similar.
Waste of time, gas and effort so far. Time to walk away for today and see what tomorrow brings after a good nights sleep....
Porosity and low penetration everywhere.
Tried sandblasting, flap wheels, cleaners, preheating and even several wipe downs with lacquer thinner and acetone. No dice. That cast just will not take a good weld. I can see where the contaminants are trying to “bubble up” through the weld puddle and just ruining everything. It’s so bad, I can’t even get a puddle to form properly to run a decent bead.
Only thing I can think of is to drop it in the oven at around 300-400F for a couple hours and try to boil the contaminants out of the porous aluminum casting so I will have at least a fighting chance of getting it to will weld properly.
Jeez, what a mess. At this rate, I might be chucking the whole LT1 intake in the trash (well, actually, I’ll prob end up just smelting it down to ingots).
I just might end up sticking with the oem TPI or maybe trying to find a used mini ram or similar.
Waste of time, gas and effort so far. Time to walk away for today and see what tomorrow brings after a good nights sleep....
- Thread starter
- #117
Alright. I'm going to admit defeat here.
After trying multiple settings for WS, V and travel speed as well as cleaning, preheating, etc, it seems I can get the welder to transition back and forth between globular and spray transfer. When it goes into spray, it gets lots of penetration to the point it will blow right through 1/4" thickness if I'm not careful.
When it goes globular (or sometimes sounds like a short circuit arc kicking in and out) it just lays ropey turds/balls on the surface.
Not to mention, I can't seem to end an arc without wasting a tip or having a big blob of molten Al bond to the tip or the shield. It's either get it in spray/glob and roast a tip, or no penetration at all.
So, I admit defeat. I'm going to bolt it into the Jig and use the MIG to tack the other pieces in place and drop it off somewhere to have it properly TIG-d.
It will do Aluminum, but it only seems to work for me on billet or bar stock for me. I;m guessing the cast (and the heat sink mass) is just too much for my Lincoln 180.
This piece of cast is just above the ability of both the welder and the weldor....
After trying multiple settings for WS, V and travel speed as well as cleaning, preheating, etc, it seems I can get the welder to transition back and forth between globular and spray transfer. When it goes into spray, it gets lots of penetration to the point it will blow right through 1/4" thickness if I'm not careful.
When it goes globular (or sometimes sounds like a short circuit arc kicking in and out) it just lays ropey turds/balls on the surface.
Not to mention, I can't seem to end an arc without wasting a tip or having a big blob of molten Al bond to the tip or the shield. It's either get it in spray/glob and roast a tip, or no penetration at all.
So, I admit defeat. I'm going to bolt it into the Jig and use the MIG to tack the other pieces in place and drop it off somewhere to have it properly TIG-d.
It will do Aluminum, but it only seems to work for me on billet or bar stock for me. I;m guessing the cast (and the heat sink mass) is just too much for my Lincoln 180.
This piece of cast is just above the ability of both the welder and the weldor....
10/10 for effort man!!
Good on ya for stepping back for a day and then coming back at it.
You’ve given it your best,
Still following.
Graham
Good on ya for stepping back for a day and then coming back at it.
You’ve given it your best,
Still following.
Graham
- Thread starter
- #119
I think I have a plan for where I want to go with the car.
It’s a cinch that I’ll never own a ZR1 C4. Don’t have the $$$ to buy one and even if I did, there probably isn’t more than 1 or two in all of atlantic canada. Hell, even a regular C4 is a fairly rare sight around here.
But, just because I can’t buy a ZR1, that doesn’t mean I can’t have some ZR1 level fun.
Being a convertible, the vette is already compromised (compared to a coupe).
But it does have the full z52 package, which is essentially the same as the Z51 the ZR1 gets except for softer springs.
The Vert is a 700r4, which is also down a step from the 6 speed.
That leaves the LT5 vs my L98. Obviously, there’s no contest there. LT5 blows the L98 right out of the water.
So I’m going to build up the L98 to the HP level of the LT5. Namely, I’m going to shoot for 400hp (at the crank). Thats about a 150 hp jump. Attainable, but not super easy to get there. That will let me dip into ZR1 fun without actually having to own one. 400 BHP is more than enough for me on the street.
The car also needs paint. I’ve got it looking good, but there’s only so much you can do with paint correction and touch ups.
The wife wants me to paint it blue, but I’m leaning towards keeping it black.
The rear spoiler has to go. I’ve never liked it. Too big and too “ricey”. The lower bodywork I’m a little more unsure about. One day I like it, the next day I want just the clean C4 body styling.
I’m sure more of the plan will develop as I sit in the garage over winter and stare at that big black body in hibernation....
It’s a cinch that I’ll never own a ZR1 C4. Don’t have the $$$ to buy one and even if I did, there probably isn’t more than 1 or two in all of atlantic canada. Hell, even a regular C4 is a fairly rare sight around here.
But, just because I can’t buy a ZR1, that doesn’t mean I can’t have some ZR1 level fun.
Being a convertible, the vette is already compromised (compared to a coupe).
But it does have the full z52 package, which is essentially the same as the Z51 the ZR1 gets except for softer springs.
The Vert is a 700r4, which is also down a step from the 6 speed.
That leaves the LT5 vs my L98. Obviously, there’s no contest there. LT5 blows the L98 right out of the water.
So I’m going to build up the L98 to the HP level of the LT5. Namely, I’m going to shoot for 400hp (at the crank). Thats about a 150 hp jump. Attainable, but not super easy to get there. That will let me dip into ZR1 fun without actually having to own one. 400 BHP is more than enough for me on the street.
The car also needs paint. I’ve got it looking good, but there’s only so much you can do with paint correction and touch ups.
The wife wants me to paint it blue, but I’m leaning towards keeping it black.
The rear spoiler has to go. I’ve never liked it. Too big and too “ricey”. The lower bodywork I’m a little more unsure about. One day I like it, the next day I want just the clean C4 body styling.
I’m sure more of the plan will develop as I sit in the garage over winter and stare at that big black body in hibernation....
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- Thread starter
- #120
Well, as life always does, it jumped up and bit me in the butt.
On friday, my back went out. Spent the night in the hospital under some heavy pain killers/muscle relaxers and am now hobbling around the house. It’s an old injury that jumps up and drops me every now and then. Broke it on a medivac a couple hundred miles off Sable Island in 2002 and now have a disc bulge at L5/S1 that the MRI says “nerve impingement”. Which is a nice way to say it’s going to drop you like a sack of bricks when you least expect it and for no particular reason.
Work on the Vette will have to be “curtailed” for the next while (on the order of months, at the least). Hard to bend over to reach anything below my waistline right now and as we all know, the Vette is...loooowwww.
To add to the misery, money has gotten kind of tight for the next couple months.
So the Vette will be mostly linited to some polishing work and a few fixes (ie: AC).
It also has me rethinking the plans.
Not sure if it will be done anytine soon, but I sure like the idea of a 427 Ci small block under that long, low black hood.
But...the upside is (out of our stable of vehicles) the Vette is the most comfortable vehicle I have for my back. The reclined position is the best for my back and the C4 has a very nicely “open” seating postion. It’s just the getting in (and out) thats a bit of a challange....lol!
On friday, my back went out. Spent the night in the hospital under some heavy pain killers/muscle relaxers and am now hobbling around the house. It’s an old injury that jumps up and drops me every now and then. Broke it on a medivac a couple hundred miles off Sable Island in 2002 and now have a disc bulge at L5/S1 that the MRI says “nerve impingement”. Which is a nice way to say it’s going to drop you like a sack of bricks when you least expect it and for no particular reason.
Work on the Vette will have to be “curtailed” for the next while (on the order of months, at the least). Hard to bend over to reach anything below my waistline right now and as we all know, the Vette is...loooowwww.
To add to the misery, money has gotten kind of tight for the next couple months.
So the Vette will be mostly linited to some polishing work and a few fixes (ie: AC).
It also has me rethinking the plans.
Not sure if it will be done anytine soon, but I sure like the idea of a 427 Ci small block under that long, low black hood.
But...the upside is (out of our stable of vehicles) the Vette is the most comfortable vehicle I have for my back. The reclined position is the best for my back and the C4 has a very nicely “open” seating postion. It’s just the getting in (and out) thats a bit of a challange....lol!
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